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Discussion Starter · #1 ·
I have a 76 Spider which was restored several years ago. :) There is 100K miles on the chassis and 5K since the rebuild. As part of the process, I thought I had a water leak (but nooooo, that was the subsequent upper end rebuild of the engine:() and had the radiator pulled and sent out. Since the upper end work, the temperature gauge has normally reached 212 on the highway in a short period of time and occasionally exceeded that reading. I have successfully burned off the reading by using the heater, but, after changing the thermostat, the reading is the same (maybe only slightly lower, but not at the old, 185).

When the engine was being redone, I had the hotter Wes Ingram street cams put in to match the pump, and the head was shaved a bit. I recently got a laser minitemp guage and things did not seem to be as hot as on the dash guage, the hottest reading I got was at about 195 at the top of the radiator. Interestingly, after reaching operating temperature, immediately after shutting down the engine, the temperature readings were cooler at the bottom of the radiator, reaching about 120 near the bottom and 105 at the bottom (which indicates to me it may be clogged, even after being sent out).

I can think that either the problem is the water pump not pumping or that the radiator is clogged preventing flow through. Anyone have any thoughts? Prior to the rebuild, the gauge could have been stuck on 185 for all of its movement, except when the coolant level dropped due to the head gasket failure (so that's where the water went!:eek:).
 

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Discussion Starter · #4 ·
John,

Thanks for replying. Bleed was done (this week) by shop (not an afla specialist, but they did rebuild my engine 18 years ago) installing the thermostat. I gave them the book on the car and pointed out the top of waterpump bleed point, said that there were others they shoud do per the book. I can check again, it's not that difficult.
 

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Discussion Starter · #5 ·
Just rechecked the bleed and, with the heater valve open, the radiator cap off, there was no air at the water pump or the manifold.

As an aside, when the engine was originally rebuilt, the oil pump was installed 180 deg off so the distributor #1 plug wire was connected at 8 oclock instead of 2. When rebuilding my distributor a couple of years ago, I rotated the dog at the bottom of the shaft 180 deg, so the wires would be in the right orientation. Then the top end rebuild took place, by a reputable alfa shop. Now the #1 wire appears to be at 8 oclock again. I think I need to check the firing orientation and, if I am correct, the way to do this is, with the cam lobes facing dead outwards, #1 cyl is at TDC and the distributor is at #1 for firing. Can I just check #1 to be TDC and then look at the distributor, not taking the cam cover off?
 

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Yes, just rotate the engine so that when you look down through the spark plug hole on #1 that both valves are fully closed and that the crankshaft pulley is set at "P" (Punto).

It really doesn't matter how the distributor is oriented as long as the spark plug wires are in the correct order and timed correctly.

That said, if you had a firing order that was incorrect, the engine would run very badly and it would be pretty obvious to the casual observer.

On a hot summer day at high speed, my engine can go to 210 or so.
 

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You've modified the engine and made her run a little hotter. Combine that with and older less efficient raditor and you've got your problem. The original NEW Spider radiator has just enough cooling capacity to do the job and that's about all.

Read some of the threads concerning going to a three or four row radiaor. Spend the $300 to get it done and not worry about over heating again!
 

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Discussion Starter · #8 ·
John,
OK, so the pointer is at Punto, the #1 is TDC, and looking into #1 spark hole, all I can see is piston top. Does this mean the valves are closed, or am I looking in the wrong spot? Distr. is pointing at 2 oclock, but that is wire for cyl 4.
 

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Radiator should be hotter at the top (inlet) and cooler at the bottom (outlet)...so eliminate that. A clogged radiator would show up as a hot at top...and then all of a sudden as you pan down you see a dramatic drop in temp...not a gradual drop in temp.

Did you bleed the upper with the heater valve open, and the car running?

My bet...timing. You seem to be already alluding to a timing issue. Piston 1 TDC (up) and valves closed, distributor rotor pointing towards the radiator, replace distributor cap, start wires where rotor was pointing with 1, and then 3,4,2 clockwise. Then get a timing light on her and adjust her to specs.

Other alternatives.....bypassed heater core without restrictor, running lean, faulty gauge.

Best Regards,
John M
 

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Discussion Starter · #10 ·
John,
Thanks for the input. Car was not running when I bled the upper, but it was kind of a recheck on my shop, which I hope did it right in the first place. I'd think the bubble would have risen to the top, but I'm strictly an amateur here.

Timing. From my description of the #1 at Punto and not being able to see anything through #1 plug hole aside from cyl top, are the valves closed and should dizzy be on #1 cyl, 2 oclock??

Speaking of the dizzy, I'm getting new springs from NAPA and hope that they will help the retard situation when we get to that. I was fooling around with the distributor about two years and 1000 miles ago.

Other issue may be shaving head increasing compression and making engine run hotter under all conditions.

By the way, I tested the thermostat that I took out of the car and it was opening around 185. The gauge readings seem to indicate that the new (actually my used gauge from my spare parts engine) is acting the same way.
 

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Discussion Starter · #11 ·
BTW, the car runs great, just the gauge reads high and I want to make sure I'm not cooking the aluminum into an expensive stew. Then there is the ignition timing issue that I want to make sure is right...

Thanks everyone for all of your help so far.
 

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Timing. From my description of the #1 at Punto and not being able to see anything through #1 plug hole aside from cyl top, are the valves closed and should dizzy be on #1 cyl, 2 oclock??
If you want to find TDC: With the crank at TDC and piston 1 up, #1 valves closed, lobes on #1 cams pointing outboard (pull the valve cover to verify), distributor rotor pointing towards the nose of the car....you will have TDC....or close enough. While you have the valve cover off and the crank aligned at TDC, check the cams to make sure they are on their timing mark (1st journal caps...towards front of car). Stock setup is with rotor pointing forward if oil pump was installed correctly. Where ever its pointing..that is number 1.... and the distributor head can be adjusted to match up while leaving adjustability for advance/retard.

If she is running good...then you either have you plug wires right or 180 out. How about just retarding the distributor a little and see if your temp goes down a bit. Shaved head....doubt that is the problem. And 212....not a worry really. The only concern to my mind is if you have too much advance or running lean.....and detonating.

Best Regards,
John M
 

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Discussion Starter · #13 ·
Old history, oil pump 180 off. Cam lobes out, Punto mark, #1 at 8 oclock, therefore everything is in proper phase, up top. Getting dark here, tomorrow I'll check the timing if I have a minute. The retard spring has been historically weak, I hear NAPA has a replacement from a GM kit (thread 149235) and I'm going to try to pick that up tomorrow.
 

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Sounds similar to what I had..

Vernon, I have a 76 as well. I have had it since 1983. Well, anyway I rebuilt the engine about 3 years ago. While I was doing that I changed to motoronic cylenders and pistons, and eurocam. My engine was running hotter than it had before and I attributed it to the hotter setup.

My cure? A fan shroud. The car had not had one since I had bought it.

Might help you as well. Just a thought.

Ted

p.s. I should also mention that I had the radiator checked, and I do not have a restrictor in the upper hose.
 

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....which indicates to me it (the radiator) may be clogged, even after being sent out.
Vernon:

Yea, that would be my guess. You describe the radiator as having been "sent out", but what the heck does that mean? A schlocko radiator shop may have just soaked it a bit, sprayed it black, and called it done. RandallM offers the right solution: recore it with a heavier core material.

It has been my experience that Alfas tend to run cool. The batwing oil pans make them air-cooled, as well as water cooled. Stuff like fan shrouds, igniton timing, cam overlap, yadda yadda can make a difference in running temperature, sure. But, the biggie is how well your radiator flows, and of course, where your thermostat opens. It's worth getting the other stuff right, but if your engine is suddenly running significantly hotter, then look at the cooling system first.

I doubt your water pump is the issue. They fail when the bearing goes and takes out the seal, leading to leaks. By the time that the impeller corroded so much that the flow rate was reduced, the bearing would have long since expired.
 

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Discussion Starter · #17 ·
Saturday update...
Changed the springs in the distributor to the GM/Napa kit from another thread, lubed plate, silver springs too strong, no advance, no power, changed back. Cleaned distributor cap and contacts. Retarded the timing by rotating the distributor about 1/4 inch clockwise, no power, rotated back. Opened cold idle opening to full open to help cold idle speed. Hooked up sears tach, penske timing light, found timing was spot on at both 800 and 4600 RPM (what luck!). Test drive showed running temp slightly lower (205+ hwy), going back to 190 on city streets after 10 mi of highway driving at 70, but hot idle at 1100. Need to look at rod adjustment for air at hot idle. Cold idle much better than before (previously undrivable without hand throttle assist). Altogether a pretty good morning at the hobby.:)
 
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